John K Jordan
>>>Rather than getting new battery innards it seems like a better idea to buy the adapter to the 20v slide in battery
I bought the Dewalt kit with charger, adapter, and two 20v lithium ion batteries. Smaller and lighter weight than the 18v batteries.
Worked great, lots of power. However, after some months both batteries quit charging to full power. Since they both started this at the same time, I wonder if the charger is the problem. I have not yet tried contacting Dewalt.
I've had better luck with 3rd party replacement batteries. I bought two of these, might get some more since I have a lot of Dewalt cordless tools.
If I had to start from scratch, I'd buy some other brand than Dewalt. Hitachi, Milwaukee, etc.